Summary

The preceding paper showed that those conditions that ought to stimulate reacylation of lysolipids in cells can increase cell adhesions. Similarly we found that conditions that would be expected to lead to the accumulation of lysolipids in the cell surface diminish cell adhesion. This paper reports on the answers to the following questions. (1) Is reacylation of lysolipids in the cells stimulated by an external supply of CoA, ATP and a fatty acid? (2) Does this reacylation lead to the incorporation of exogenous fatty acid in the plasmlemma? (3) What range of fatty acids can be incorporated into the plasmalemma and into what compounds? (4) Does the plasmalemma contain the enzyme systems to effect this turnover, namely phospholipase A2, a CoA-ligase and an appropriate acyl transferase(s)? (5) Do lysolipids accumulate in the plasmalemma under conditions which diminish cell adhesion? We find that saturated fatty acids in the range C14–C18, and some unsaturated fatty acids are incorporated into the plasmalemmae of these neural retina cells. About 20% of the plasmlemma content of fatty acids can be turned over in 30′. Incorporation is mainly into phosphatidyl choline, serine and ethanolamine in both R1 and R2 positions. The plasmalemmae contain the enzymes to effect the turnover. Isolated plasmalemmae are active in this turnover. Incubation of the plasmalemmae with phospholipase A2 leads to an accumulation of lysolipids. Very low levels of phospholipase stimulate turnover, possibly endogenous phospholipase activity is the rate-limiting step in the system. These findings are discussed in relation to the possible mechanisms by which lipids might affect adhesion.

Pavan Vedula and Anna Kashina propose a new concept, the actin code, which encompasses the regulation of the essential functions of mammalian actins at the nucleotide level, rather than at the level of amino acids.

“To me, there are no real boundaries between chemistry, biology, physics and maths.”

Tony leads a group at the Mechanobiology Institute in Singapore, focusing on dissecting the structure–function relationship that underlies protein complexes that are involved in cell migration and adhesion. He shares his thoughts on why you don’t necessarily have to choose between the different branches of science that you find fascinating.

We also feature interviews with first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Check out our recent First Person interview with Julia Abitbol.

The second in our series of cell dynamics meetings now turns to organelles. This May 2019 meeting in Lisbon, Portugal, aims to bring together scientists studying the interface between organelles and the cytoskeleton at different scales and perspectives using a range of model systems. Find out more and register your interest here.

We are currently seeking proposals for four Workshops to be held in 2020. Do you have an idea for a Workshop? Please let us know and you could be one of our 2020 Workshop organisers. You focus on the science, we focus on the logistics. We are particularly keen to receive proposals from postdocs. Deadline date for applications is 25 May 2018.

Meet the preLighters! In the latest interview with our preLights community, the preLights team caught up with James Gagnon, Assistant Professor at the University of Utah, to talk about his research, how science can be made more open, his enthusiasm for the preLights project and the fun sides of being a junior PI.

Alexander García Ponce investigated how hematopoietic stem cell (HSC) cross the vascular wall and reach the bone marrow as part of his PhD project, with an aim to improving the outcome of HSC transplantation for individuals with leukaemia. A Travelling Fellowship from JCS allowed Alexander to advance his research at the Sanquin Blood Bank in The Netherlands. Read more on his story here.

Where could your research take you? Join Alexander and apply for the next round of Travelling Fellowships from JCS by 25 May 2018.